Houston, We Have a Space Force

A new military service isn’t needed to compete above the Earth.

For most Presidents an event about space regulation wouldn’t produce headline news, but then there’s President Trump. At such an event last month Mr. Trump ordered the Pentagon to develop a de novo military branch dedicated to space. This plan is not ready for the launchpad, even if Mr. Trump is right about the threat.

President Trump’s idea of a “separate but equal” Space Force isn’t novel: The House last year passed a proposal for an independent space branch, and Congress ended up commissioning a study. The argument is that...